Cocoa Fundamentals Guide: Table

**Table 2-3** Class clusters and their public superclasses
Class cluster	Public superclasses
`NSData`	`NSData`
`NSData`	`NSMutableData`
`NSArray`	`NSArray`
`NSArray`	`NSMutableArray`
`NSDictionary`	`NSDictionary`
`NSDictionary`	`NSMutableDictionary`
`NSString`	`NSString`
`NSString`	`NSMutableString`